Combustion system



. 1,634,570 July 5.-,1927 A. J. BoYNroN CoMBUsTIoN sYsTEM Filed 001;. 16, 192.4 l 2 vSheets-sheet 2 Patented July 5, 1927.l

UNITED STATES PATENT OFFICE.

ARTHUR J. BOYNTON, OF WILMETTE, ILLINOIS, ASSIGNOR, BY 'MESNE ASSIGNMENTS, T VICTOR CHEMICAL WORKS, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

COMBUSTION SYSTEM.

Ihis invention has to do With improve ments in combustion systems. The invention has to do with the burning of gases and fumes Where the purpose of thecombustion is not merely the utilization of the heat contained in the gases of combustion, but also the combustion of elemental substances resident in or carried by the gas, Where the primary purpose is the use "of the products of combustion for other purposes than the utilization of their heat of combustion and sensible heat. F or example, the system of the present invention is intended for the production of oxides from elemental subl5 stances cit-her gaseous or solid or in the form offumes, the solids and fumes being resident in and carried by the gases. The system of.

the present invention also is for the production of higher oxides from substances al?v 2o ready partially oxidized Where the process of the combustion is to use the oxidized substances for other reasons than that of their sensible heat and the heat of combustion.

' The combustion as practiced according to the present system necessarily also results in the generation of heat, but this heat generation is largely an incident to the fundamental purpose of the invention which Y is the control of the combustion in such a: :so Way as to give the desired end products which it is sought to produce.

The application of this system of combustion will be better understoodA by way of illustration or example; but in giving the :i5 same, I Wish it clearly understood that such example is purely illustrative and is `not intended as a limitation on the process or l practice of the invention, except as provided in the claims.

As illustrative, reference may be had-to the production of phosphoric acid, P205, by the operation of a vertical shaft furnace in conjunction with a series of hot stoves. In such case, the phosphate rock together with the 45 necessary amount of coke and suitable flux- 'ing agents is introduced into the upper end of a vertical shaft furnace, such, for example,

as a small blast furnace. The operation in this furnace is so regulated that the gasestaken off at the top include carbon monoxide and fumes including phosphorus fumes. These products are then carried to the hot stoves used'for'preheating the air blast of the shaft furnace. The gases and fumes are ,burned in the hot stoves on alternate periods of combustion, and air, so as to Preheat the air blast in the Well understood manner. The burned products of combustion from thehot stoves may then be taken through a suitable cooler and finally delivered to a precipitation apparatus wherein the P205 ie recovered. v

The successful practice of this process, however, requires that the combustion inthe hot stoves shall be practically perfect, sub' 65 stantially Without excess of oxygen. At the same time a., sufficient amount of oxygen for complete combustion must be supplied so as to insure the proper conversion of the phosphorus .bearing fumes.

ln the above processa practically perfect control of the oxygen requirements at the hot stoves, and the consequent ability to produce the desired end product, is the fundamental and controlling feature, and the actua-l production of heat inthe hot stoves is incidental to thisfundamental object. In fact, if more convenient or desirable, the combustion could be practiced in apparatus other than hot stoves, the air blast in such case being preheated in some other Way, if pre- `heating should be a desirable or necessary requirement. l

The perfect combustion of the gases and fumes in the hot stovesdepends largelyupon their composition. The combustion must be carried forWardWith vthe total oxygen requirements of the carbon monoxide and phosphorus in View, and not simply in such a manner so as to satisfy the combustion requirements of the carbon monoxide gas.

The supply'of gas and fumes will necessarily fluctuate from time to time and the oxygen requirements should be immediately varied in accordance therewith. In'order 95 to insure complete combustion substantially Without excess of oxygen at all times. the air supply to the hot stoves should be so controlled from instant to instant asto maintain the proper ratio of air to gas and fumes 10C at all times. The perfect combustion can be ensured by so controlling the supply of air as compared to gas and fumes that there is maintained a definite relation between static pressures of the combustible gas and fume and of the air and corresponding delinite proportions between the areas of exit from the burner of the gas and fume 'and of the air. Certain regulators have heretofore been devised lfor instantaneouslyv so controlling thel air supply` as to 4maintain l this ratio, including the type of device shown I out of apparatus for practicing the' present invention; and

Fig. 2 shows '1n fragmentary vertical section a type of burner construction of the 'general type of 4the aforesaid Steinbart patent.

In the layout illustratedin the drawings,

the initial stages of the `process are practiced stoves may be of any suitable typ in a .vertical shaft furnace 3 which is illustrated as being. of the typeof a small blast-- furnace. It includes the hearth section 4, bustle pipe 5, tuyres 6, bosh 7, throat sertion 8, cinder notch 9, charging head 10 and downcomer 11 of the usual form of the blast furnace. Ordinarily, however, the blast furnace used'in the present invention, when a blast furnace is used, will be relatively small and have a height of probably not to exceed twenty-five feet.' The hot stoves are designated by the numerals 12. 13 and 14 respectively. The air blast for the bustle 5 1s delivered through a pipe 16 which connects tothe various hot stoves by the connections 17 under control of dampers.

e, such as the familiar 'Cowper type.

The air blast delivered to the hot stoves is supplied by the main 1'8 through the connections 19 under control of suitable dampers.

The gases and fumes delivered from the b'last furnace downcomer 11 are carried to the hot stoves by a flue 20. In some cases, the dustcatcher 21 may be placed-between the dowucomer 1l and iue 20 so as to remove rcertain materials, but the fumes should not be removed, since these are one of the primary objects of the operation conducted in the vertical shaft furnace. The flue 2l) is connected to the different hot stoves by connections 22 under control of the proper dampers. Air connections 23 serve for admission of the air for combustion to burn the gases and fumes supplied through the connections 22. c

A products of combustion flue 24 is provided for removing the products of combustion from the different stoves by the connectionsl 25 under control of suitable dampers in the manner well understood in the art.

Vihen any given stove is being operated on gas, the gas is admitted throuvh the con- 1.1ecton'22,the proper air for combustion be- These hot are then delivered to the flue 24 and conducted to the subsequent apparatus. When any given stoveis being operated on air, the same is admitted from the flue 18 to such stove and passes through the stove Vand is heated bythe hot checker work thereof. This hot blast is then delivered through the hot blast main 16 to the bustle pipe. The above operations are well knownand-understood in the art.

In order to secure the necessary accuracy ofcontrol of combustion of gases and fumes delivered to each hot stove, there is provided a regulator, such, for example, as that illustrated in Fig. 2. rIhe het stove has the opening 26 provided with an end nipple 27. Back of this end nipple is a combustion nozzle 28 including a central gas opening 29 surrounded by an annular air passage 30. The area-s of the opening 294 and air passage 30 are in definite ratio and do notvary. Air is delivered to this passage 30 from a box 31 which surrounds the throat 32 through which the gas and fume are delivered. As a re- 'sult the combustion begins at the point where the gas and fumes come into contactwith the surrounding layer of air. l

The gas delivered through the throat 32 comes from a box 33 preferably provided with a transverse partition 34. This partition reaches the full height of the box 33, but does-not reach the full width thereof, so that the gases and fumes are allowed to swirl around the side edges of the partition. The gases and fumes are delivered to this box 33 by a connection 35 which in turn connects to the pipe 20. In Fig. 1, which is more or less diagrammatic in form, the pipe 2O is shown as below the position of the connection into the hot stove, whereas in Fig. 2, which is a more correct illustration, the connection 35 is shown as reaching downwards towards the hot stove.

They air delivered by the box 31 comes in the first instance from a flue 36 and through a throat 37. A butterfly valve 38 is placed in the throat 37 and is controlled by a lever arm 39 at the outside of Vthe throat. This lever arm in turn connects by a bell crank 40 and links 41 and 42 with a piston inside of a regulator 43. Pipes 43a and 43'? connect the chambers 31 and 33 with the sides'of the piston so that the valve 38 is operated according to the differential pressure. This regulator is of the general type of the aforesaid Steinbart patent,and is so constructed that the amount ofopening of the butterliy valve is proportional to the relation of the static pressure of the combustible gas and fume inthe box 33 as compa-re l to the static pressure of the air in the box 31.

The perfectly oxidized materials coming from the pipe 24 are passed through a cooler 44 and thence by a connection 45 to a suitable precipitation apparatus' designated generally by the numeral ,46, rIhis may be of any suitable form, such as an electric precipitation apparatus of the type of the Cottrell United States Patents Nos. 895,729, issued August 11, 1908; 945,917, issued J anuary 11, 1910; 1,016,476, issued February 6, 1912; 1,035,422, issued August 13, 1912; and 1,067,974, issued July 22, 1913. Y

These electricprecipitation devices include separated electrodes located in a passage through whichfthe material to be treated is passed, said electrodes being subjected to high potential electric currents, so that the gases flowing between them are subjected to a severe electro-static action. In case there should be present unoxidized products inthe gases flowing through these Cottrell devices, there would be serious danger of explosionv due to ignition of some' of the gases by electric sparks. This is -an additional reason why it is very desirable to be able to deliver the gases from the burners to the precipitation apparatus substantially without excess of oxygen and yet inv fully oxidized condition.

In some cases the amount o'f gas and fumes delivered from the vei'tical shaft furnace will be greater than necessary to supply the heat needed for operation of the hot stoves to the degree necessaiy for the hot air blast. When this is the case there will be a surplus of gas and fumes available for the heating of boilers or other devices. I have, therefore, illustrated in Fig. 1 a boiler diagraminatically by the numeral 47. The same is fed with the surplus gas by a connection 48 from the flue 20; and the oxidized materials produced in the boiler furnace by consumption of the gas and fumes are then returned to the products of combustion iue 24 by a connection 49. In the case of combustion of surplus materials, the same should also be perfectly oxidized if possible; and it is, therefore, contemplated that the combustion of such surplus gas and fumes shall also be conducted under control of a regulator of the general type of the aforesaid Stamps and Steinbar-t patents. 1

It is'also noted that inasmuch as the conibustioii of the gas and fumes is primarily for the purpose of generating certain desired end products, the same may be conducted either in conjunction with heat absorbing devices for the useful application of the heat generated by the combustion, or independently of such heat absorbing devices. For example, a burner of the general typeof the aforesaid Stamps and Steinbait patents might be used to advantage for the combustion of the gas and fumes within a closed chamber, iii such a manner as to produce tablhishing a definite relationship between the static pressures of the combustible gas and p fumes and of the air, and corresponding def- Yimte proportions between the areas of exit from Ythe burner of the gas andfuine and Y of( the air.

While I have herein shown and described only a single embodiment of the features of my present invention, still I do not intend to limit myself to the same, except as I may do so in the claims.

I claim:

1. Apparatus for the recovery of phosphoric acid or other oxides from raw mateiials comprising in combination a vertical shaft furnace having means for introduction of the raw materials and fuel and fluxing material at the top, together with a Silit-- able gas and fumes top delivery connection and having suitable tuyres in its lower portion, of hot stoves in conjunction with said furnace, hot blast connections therefrom to the furnace tuyercs, a connection for the delivery of gas and fumes from the furnace to the hot stoves for combustion therein of gas It isl and fumes necessary to heat the air blast for )ressure between 0ras and fumes su l and air supply'thereto for insuring substantially perfect combustion therein for the purposes specified, a' cooler, products of combustion connections from the hot stoves and auxiliary heat generator Ato the cooler, Cottrell apparatus, and products ofcombustion and fumes connections from the. cooler thereto, substantially as described.

2.. Apparatus for the recovery of pliosphoric acid or the like from raw materials comprising in combination a furnace having means for introduction of the raw materials and fuel and fluxing material. together with a suitable gas and fumes delivery connection and having suitable tuyres, of hot stoves .in conjunction with said furnace, hot blast connections therefrom to the furnace tuycies, a connection for the delivery of gas and fumes from the furnace to the hot stoves forl combustion there-in of gas and fumes necessary to heat the air blast for the furing to the differential of pressure between gas and fumes supply and air supply thereto for insuring substantially perfect combustion therein lforthe purposes specified, a cooler, products of combustion connections from the hot stoves and auxiliary heat generator to the cooler, Cottrell apparatus, and products of combustion and fumes connections from the cooler thereto, substantially vas described.

3. Apparatus for the recovery of phosphoric acid or the like from raW materials comprising in combination a furnace having means for introduction of the raw materials and fuel and fluxing material, together with a suitable gas and fumes delivery connection and having suitable tuyres, of hot stoves in conjunction with said furnace, hot blast. connections therefrom to the furnace tuyres, a connection for the delivery of.

gas and' fumes from the furnace to the hot stovesfor combustion therein of .gas and fumes necessary to heat the air blast for the furnace,A regulators at the hot stoves operable -according to `the differential of pressurebct-ween gas and fumes supply and air supply thereto for insuring substantially perfect combustion therein for the purposes and fumes from the furnace to the hot stoves for combustion therein of gas and fumes necessary to heat the air blast for the furnace, regulators at the hot stoves oporable according to the differential of pressure between gas and fumes supply and air supply thereto for insuring substantially perfect `combustion therein for the purposes specified,r Cottrell apparatus, and products of combustion and fumes connections thereto, substantially as described.

5. Apparatus for the recovery of phosphoric acid or the like from raw materials comprising in combination a. `furnace, havingr means for introduction of raw materials and fuel and iiuxing material, together with a suitable gas and fumes delivery connection and having suitable tuyres, of regenerating apparatus in conjunction with said furnace, hot blast connections therefrom to the furnace tuyres, a connection for the delivery of gas and fumes from the furnace to the retion therein for the purposes specified, suitable a paratus for recovering the phosphoric acid rom the products of combustion from the regeneratin apparatus, and products of combustion an fumes "connections thereto,

ysubstantially as described.

6. Apparatus forv the recovery of phosphoric acid or the like from raw materials comprising in combination a furnace having means for introduction of the raw materials and fuel and fluxing materiahtogether with the suitable gas and fumes delivery conneo -tion and having suitable tuyeres for the introduction of air blast, of a closed combustion chamber, connectionsfor introduction thereinto of gas and fumes-delivered from the furnace and air for combustion, a regulator in conjunction with said connections operable according to kthe differential of pressure between gas and fumes supply and air supply thereto for insuring substantially perfectcombustion in said closed chamber for the purposes specified, Cottrell apparatus, and products of combustion and fumes connections thereto from said combustion chamber, substantially as described.

7. Apparatus for the recovery of phosphoric acid or the like from raw materials comprising in combination a furnace having means for introduction of the raw materials and fuel and fluxing materials, together with a suitable gas and fumes delivery connection and having suitable tuyres for the introduction of air blast` of a 4closed combustion chamber, connections for the introduction thereinto of gas and fumes delivered from the furnace and air for combustion, a

regulator in conjunction with said connections operable according to the differential of pressure etween gas and fumes supply and air Supply thereto for linsuring substantially. perfect combustion in said closed chamber for the purposes specified, suitable apparatus for recovering desired end produ'cts, and products of combustion and fumes connections thereto from' said combustion chamber, substantially as described.

8.' Apparatus for the recovery of desired end products from raw materials including a furnace for the reduction of said raw ma.- terials together with production of producer gas and fumes therein, a closed combustion chamber, gas and fumes connections'from the furnace to said combustion chamber, an air connection to said combustion chamber, a regulator in conjunction with the gas and fumes and air connections and combu'stion chamber operable according to .the differential ofressure between gas and fumes supply an air supply thereto for insuring substantially perfect combustion therein for the ,purposes specified, Cottrell apparatus, and

products of combustion and fumes connections from the combustion chamber thereto,

, substantially as described.

' end products from raw materials includingV 9. Apparatus for the recovery of desired a furnace for the reduction of said raw materials together with production of producer gas and fumes therein, a closed combustion chamber, gas and fumes connections from the furnace to said combustion chamber, an air connection to said combustion chamber, a regulator in conjunction with the gas and fumes and air connections and combustion chamber` operable according to the differential of` pressure between gas and fumes supply and air supply thereto for insuring subl stantially perfect combustion therein for the l purposes specified, suitable apparatus for the` furnace and air for combustion, a regir,

lator in conjunction with the gas and fumes vandfair connections'whereby the proportionsfof combustible gas and'fume and of air are accurately controlled by establishing a definite relation between the static pressures of the combustible gas and fume and Tof the air and corresponding denite proportions between the areas of exit of the gas and fume and of the air for the purposes specified, suitable apparatus for recovering desired end products, and' produlcts/of'combustion and fumes connectionsth'ereto from said combustion chambery.' substantially as described.

1l. Apparatus for the recovery of the de'-l siredend products from suitable raw materialsA including a furnace wherein said raw materials are reduced with production of producer gas and fumes, a combustion chamber, connections from the furnace. to the combustion chamber for delivery of producer .gas and fumes from the furnace thereto, an

airv supply connection to the' `combustion chamber, means for accurately controlling the proportions of combustible gas and fume and of air by establishing a definite relation ybetween the static pressure of the combustible gasand fumes and of the air and corresponding definite proportions between the4 .areas of exit of the gas and fume and of the air for the purposes specified, and means for recovering desired end products from the products of combustion of said chamber, substantially as described.

l2. Apparatus for the recovery of desired end products from suitable raw materials including a furnace wherein said raw materials are reduced with production of producer gas and fumes,connections from the furnace for the delivery of producer gas and fumes therefrom, a regulating burner in` conjunction with said connections at a point of combustion, whereby the proportions' of combustible gas and fume and of air are accurately controlled by establishing adeiinite relationship between the static pressures of the combustible gas and fume and of the air and corresponding delinite proportions between the areas of exit from the burner of the gas and fume and of the air for the purpose specified, and means for recovering desired end products from the products ofv combustion of said chamber,

substantially as described.

ARTHUR J. BOYNTON.- 

